New coolant temp sending unit showing maxed out

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wassup77

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Hey guys I got a weird issue. On my 91 suburban 350 tbi, I had to replace my coolant temp sending unit. I bought a new one from autozone and it had the correct plug end and fits the whole in the head, but as soon as you turn the key On it goes to the maxed out position on the gage. The previous one worked fine until I broke it changing spark plugs. Have any of you ever had this problem? I’m thinking either it’s defective or it’s the wrong sending unit. Any advise is appreciated.
 

wassup77

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Well I don’t know of The sending unit was defective or if it was the wrong one, but I changed it again and now the gauge works.
 

73c20jim

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There are two different senders.

One for idiot light and one for gauge.
 

Itali83

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Yeah, I’m dealing with the same problem. I tested the new sender and it’s defective. It’s a direct short when it should have 650 ohms at 70 degrees.


Ben
 

AuroraGirl

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Hey guys I got a weird issue. On my 91 suburban 350 tbi, I had to replace my coolant temp sending unit. I bought a new one from autozone and it had the correct plug end and fits the whole in the head, but as soon as you turn the key On it goes to the maxed out position on the gage. The previous one worked fine until I broke it changing spark plugs. Have any of you ever had this problem? I’m thinking either it’s defective or it’s the wrong sending unit. Any advise is appreciated.
is it a one wire i assume. unplug it. what does gauge do.
 

wassup77

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1991
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Suburban V1500
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350 tbi
Yeah, I’m dealing with the same problem. I tested the new sender and it’s defective. It’s a direct short when it should have 650 ohms at 70 degrees.


Ben
You were correct. I went to Napa and got another one, and it works fine now. I hate autozone lol
 

AuroraGirl

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You were correct. I went to Napa and got another one, and it works fine now. I hate autozone lol
i am lesss pleased with most auto stores more and more but autozone is the only store open on saturdays whenever i need something on a saturday that isnt complete incompetence in the noon-night part of the day. They got a guy from texas hes into bikes I assume based on his biker apparel and bike he drives and hat but he also is smart with vehicles which means he knows a thing or two and I assume its because hes seen a thing or two. then outside of gambling on weekdays in evening or just avoiding autozone in favor of an auto-value near me but priceier, but helpful nonetheless, I would take that simply by distance.

If the morning is fresh then NAPA it is because that old fart is there like clock work and I can always ask this girl I graduated with before going. she works there too. not really knowledgeable but they have her do non-knowledge having things.... which apparently is enough for an employee at an auto store so good for them.
 

82sbshortbed

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You were correct. I went to Napa and got another one, and it works fine now. I hate autozone lol

Napa is my favorite parts store in my town. AZ can eat a d¡ck.
 

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